Motor vehicle brake



June 7, 1938. P. F. RossMANN MOTOR VEHICLE BRAKE Filed Jan. l0, 1935 Planted im; l'1, 193s Moron vaincu: nasxn Bcssmanmnetrolkmch., alllgnor'to MotorCarGompannDetrcihmcima" --w y Peter F.

corporation of Mi Appunti .mmm 1o, 1935, sei-MN. 1,252 11 calm. (ci. 1st-15m.

This `invention relates to actuator means and more particularly to actuator means employed to operate mechanism forming apart of a motor vehicle. l

An object of the invention is to provide a compact structure which is operated by `either combined physical and power created force or entirely by physical eiiort to actuate a mechanism.

Another object of the invention is to provide a linkage actuator for motor vehicle mechanism which includes power means, control valve means, and physical reaction means.

A further object of the invention is to provide a unitary actuator means, operable by a manual and power created force, in which a casing, a valve structure and physical reaction means are interdependent and interacting.

Still another object of the invention is `to provide actuator means operable through the effect of physical and power applied forces in which physical reaction means is power operated.

Other objects of the invention wiliappear from the following description taken in connection with the drawing, which forms a part-of this Aspeciilcation, and in which:

Fig. 1 is a plan view of a motor vehicle chassis having .my invention associated therewith for operating brake mechanism.V

Fig. 2 is a vertical sectional view of the actuator means in ineffective position..

Flg.3 is a similar vertical sectional view of the actuator means in eifective brake applying position.

Fig. 3a is an enlarged fragmentary portion of the valve means shown in Fig. 2.

Fig; 4 is a perspective view showing a fragment of the actuator means attached to the chassis and the brake mechanism cross rod.

Fig. 5 is a sectional view taken on line l-l of Fig. 1 showing thev brake mechanism in one of the brake drums.

Referring now to the drawing by characters of reference, a motor vehicle main frame is illustrated as comprised of side sills i0 and cross sill members il. A power unit, consisting of an internal combustion engine l! and a transmission unit I3, is supported upon the frame, and suit-,- .able driving means extends rearwardly from the transmisison unit to actuate driving mechanism contained within the rear axle structure Il. 'I'he engine is provided with the usual intake manifold I5 through which` fuel charges are moved into the engine cylinders. Y

Brake drums i6 are associated Vwith the rear 4driven wheels (not shown) and brake drums Il Aconnected respectively to arms 2i and. 22 Vxecl .brake cross rod is a casing forming aligned cham- Yand the other end of the reaction chamber. is defined by the end wall 4l of the cylindrical strucwith amable bearings extendinzfmm :u

2,119,6sof

are associated with the front s ringwheels (not shown). In each drum is arranged a pair f pivotally mounted segmental brake shoes I normally held in released position by spring 9,. Between the free ends of the pairs of shoes are actu- 5 ator cams 1 fixed on control rods I3 which are rotated by front and rearbrake rods Il'and 2l on cross shaft 23. This crossshaft is carriedulby suitable bracket means 2l' xed to the side sills Il 10 and by a bracket 25 yxed to the cross frame brace member il extending adjacent thereto. ,f

In order to actuate the cross rod or a similar regulating mechanism, I associate therewith means which is responsive to physically created 15 force or to force created physicallyV and by power. Foot lever 28 is rotatably mounted on shaft 21' fixed in a'bearing 2l extending from one side of the transmission casing. The -rod 30 of a power piston 3| is pivotally connected by link 32 with 20 an anchor eye bolt 33 iixed to the intermediate frame cross member adjacent the brake cro rod.

-The threaded stem 34'of a valve 3l is screwed into a member 36 .which is pivotally connected to the lower end of lever 26. The valve stem and 25 f piston rod are preferably arranged so that the extend substantially in axial augment.

Associated with the valve, power piston and.

bers 31, 38, and 39. Chambers 31 land 33 are de- ,30- iined by a two diameter cylindrical structure, the larger diameter portion of which contains the power piston and the smaller diameter'portion 4I ofv which contains a physical reaction piston I2. Chambers 31 and 38 are separated by a partition .35 43 suitably secured in the cylindrical structure ture. An end wall l5 is suitably fixed to the cylindrical structure and denes the rear end of 40 the power chamber. Extensions 4l project from the wall I5 and are pivotally connected to arms 41 depending from a hub 43 iixed on the brake cross shaft. 'Ihe valve is contained in chamber 3l v formed by a pair of shells I3 and Il, the shell 43 45 telescopinglthe reduced end of the cylindrical structure and being suitably secured thereon. The adjacent edges of the shells are, secured together and the adjacent .portions are of larger diameter yforming annular shoulders Il servina asvalveseats. 'A The valve is formed with a stein ,l2 which extends through axial openings in the wall I4 andthe partition wall 43 and has .a close slidingfiit The valve also has a circular iiange portion Il telescoping a portion of the stem 34 which has a close sliding fit with the open end wall of the shell Il. Coil spring I4 encircles the stem I2 in p and the reduced diameter cylindrical structure has openings therein, adjacent the partition, connecting the physical reaction chamber with atmosphere. The rcylinder wall-4l has an `open'` the chamber 3| and exerts a light pressure urg vthe shell .Il when toot'. p'rcssureis'V released from pedal 2i. The physical reaction piston in the chamber '38 is suitably held axially against a shoulder on the valve stem 52 by a nut 2l screwed on the stem.

The shell 49 has openings lltherethrough., n

' The valve structure associatedwith the casing Buch valve structure and casing have a small relative axial connecting the chamber I9 'with atmosphere.

ing l1' therethrough connecting the power cyl-l screw 59.'

'I'he valve proper is circular in #outline and is, formed 4with radially extendingA passages l0 other end. There are also openings 6| through the stem portion in the physical reaction chamb'er in advanoe ofthe' piston42. 'I'he valve and steni,v 52 thus establish communication between the' three kchambers and such chambers have Y openings connecting'thei'nV with atmosphere.

^ A pressure lowerthanatmosphericpressureis created in the chambers bysuitablej means, such as by connection with theint'ake manifoldof the engine. To'this end a conduit $4 leads from the intake manifoldl! to a reservev tank' 65 anda conduit" leads from such tank to the chamber 39. In the conduit-I4 is'fa'one-way valve 81 which'opens only when there: is a pressure' below atmospheric in the fuel inlet manifold.

The valve iiange M seals the front end of 'the 4 .shell .il and the valve `serves to selectively-seal oif the major portion of the chamber from the conduit B6 or'from i atmosphere. Rubber rings il -a'reiiixedV around thel 'front and rear' faces of the valve adjacent the periphery inv af relation to engage with the shoulders M These rubber rings are preferablyV relatively'soft and oi' suicient thicknessso that the full movement of the valve betweenextreme positions of reciprocation is relatively sm'all. When the valve ring engages the shoulder y5I 'on the shell 5I then the f conduit 66 isshut oi Viromv the maior portion vso - with ltheconduit Il.;

of the chamber 39 and the other ring is spaced from theV shoulder 5| on the shell 49 opening the maior portion of the chamber to the air` ports 55. Whenthe valve ring engages the shoulder 5I on the shell 49V communication between the majonpor'tion ot the chamber I9 and the ports 5I is shut oi'i' and the chamber communicates* In order Vthat the 'brake Amechanisuractuator the vshell 5 0 by a screw 14.

across the end of the shell ll'and is formed with f an opening through which the threadedvalve stem 34 extends. Nuts-1l and 'Ilare threaded power cylinder,

the shoulders Il is prevented by suitab1e stop means including an angular linger 18 secured to l,

This linger extends onl the stem and are spaced to engage the linger to= limit the degree e of valve'. ring;V compression Y upon engaging the shoulders Il. Y

Y ,The casing .'i'orming the power chamber, f

physical reaction chamberand the valve chams I i y.be is an' integral unit and is connected to oper- Y ate the cross shaft o!Y the brake mechanism'.

is. connected with the .foot lever 2l.

movement lrbut otherwise they form a direct actuator link between the levers 2l and 41 which are connected to move directly with the foot lever 2B and the shaft 23k respectively.- Actua tion of the cross shaft is obtained through torce exerted on the casing and such force is obtained. by combined physical Aand power eiiorts, or'entirely byphysical eiiort whenfthe power fails.

/Thev actuator meansa's shownfin Fig. 2 is in' .the position taken when the brake mechanism is entirely released, and 'in Fig. 3 the actuator l means is shown in the position taken whenz the brake mechanism is fully appliedm To apply the' brake mechanism, the foot pedal 2O Vis rocked counterclockwise, as viewed in Figs. 2 and 3,

against the action of spring 1l and the releas` ing springs 9 in thebrakemechanism.

such movementv of the lever is transmitted to theH valve structure iorcingzthe valve against shoulder 5i on the shell 4l andthereby closing the major portion ofthe valve chamber to the ports l of the .pistons therein 'isvless4 than`atmosphericl r pressure. Because of the reduced pressure inthe.

38 will move the ycylinderA toward the right which is rearwardly of the vehicle. 'Ihis casing movement rocks the arms 41 and the brake cross shaft atmospheric pressure acting f against the exterior :irontv end off the 4chamber and againstV the rpartition exposed .to chamberv 48l in a counter-clockwisedirection to apply the brakes. f'

To increase ued Vphysical force requisite to holdfthe valve against the shoulder 5l on shell 49 as the casing is moved by power toward therearof the vehicle is'required. If thefollowing movement of the vvitlverelative tothe casing is `not maintained, y

. then the valve will open and expose the chain;

bers Sland, 38 to' atmosphere, Athus equalizing the brake application a continpressures on each side of the pistons and thereby allowing Ythe brake return springs-to move thel casing tothe left. Of course if the operators foot holds the pedal lever stationary, then the valve will close again but onlyimomentarily but it' will open again as soon as the power meansiseec- It is thus seen that to increase the appli1 f" tive.

cation of the brakes, there must be a continuing pressure on the i'oot pedal and that any given brake application will be maintained by holding the'foot pedal in a fixed operative position.

Air in the portion oi?A chamber Il between the piston 42 and the partitionr 4l exerts atmospheric pressure therein. As before stated it acts to create a force against the partition serving to assist vder I on the shell' 49; It also creates a force assisting suction in the chamberv to move the' pistonA toward the left. and as the valve is v fixed axially on the valve stem unseating of the valve is thus accomplished unless foot pressure is suillclent tov hold the valveseated. `When the valve is closed, the portion of chamber 38 on the A left of the piston V42 isconnected with conduit 66, so that the pressure therein is'lower than Aon the other side of the piston, and this pressure differential provides power means for unseating the valve unless overcome by pressure by the operator on the foot pedal.l It is thus seen that physical reaction meansoperated by power forms a part of the -actuator means.v When the operator holds the foot pedal in a given position the casing will move toward the left, as previously described, and the valve will seat against the shoulder 5I on shelly 49 but as soon as power is eifectve this physical reaction means will unseat the valve unless foot pressure is increased suillcient to overcome it. Such foot pressure must therefore be applied along with the powerv developed pressure to apply the brake mechanism. 'I'he ratio of foot pressure required relative to power developed pressure is determined by the area of piston 42 relative to piston 3l. v

When pressure on the footv pedal is rbeing relieved or released, the power means is ineffective and the brake mechanism release springs will move the casing to the left and the spring 'l0 will move the foot lever in a clockwise direction'. When the actuator means is in inoperative position the spring 54 will assure seating of the valve against shoulder 5I on shell 50 to shut off the conduit 66 so that pressure lower than atmosphere is stored for use when the engine is not running, or the suction created when the engine is running is limited. The spring 'l0 will normally perform the function of holding the valve in the closed position just mentioned and spring 54 is. required only as an accessory for this purpose.

While the valve acts directly -to assist in moving the casing in opposite directions, its function in this respect is somewhat relieved by engagement of the nuts and 16 with` the finger 13 iixed to the casing, however the valve engagement is eilective prior to engagement of the nuts with the linger.

When the power means is ineffective the actuator means provides a unitary structure or link which can be moved to brake applying position by foot pressure, the valveunder such circumstance moving the casing.

It will be seen that the actuator means forms a substantially rigid linkage operable to apply the brake mechanism. Such linkage is compact and contains few parts. Physical reaction means is incorporated in the actuator means and is power operated. The valve portion of the means co operates with the other elements, andv besidesr controlling the power means `it serves to eiect operation of the power cylinder".

Although the invention has been described in connection with specific embodiments, the principles involved are susceptible of numerous other applications which will readily occur to persons skilled in the art. The invention is therefore to be limited only as indicated by the scope of the appended claims.

What is claimed is;y V

l. In an actuator-mechanism, a rigid casing having three aligned and separated chambers therein, 'means in the casing forming a'pa'ssage adapted to open tothe three separated chambers, a fixed piston in one end chamber, iluidxactuated means operable to ycreate physical reaction in the intermediatechamber, a valve movablefa limited extent in the other 'end chamber, iluid pressure means leading to the valve chamben'said valve shutting off or allowing the. passage of uid inthe passage, and physically Aoperable means conlnected to actuate said casing.

2. In'an actuator mechanism, a unitary rigid casing composed of a two diameter cylindrical shell and a'pair of shells forming a valve chamber xed to said smaller diameter shell portion, a partition in `vthe cylindrical two diameter shell separating it into a power chamber and a physical reaction chamber, a xed piston in the power chamber, a piston in the reaction chamber, iluid pressure means connected with'the valve chamber, a valve movable a limited extent inthe valve chamber, said valve connecting one end of the other chambers with the valve chamber and having the reaction piston fixed thereto, and physically operative means connected with said valve.

3. In a motor vehicle,` the combination with a brake control mechanism including a cross rod and spring releasing means, and an engine intake manifold,l of actuator means for said mechanism comprising arm means fixed on the cross rod, a pivoted foot pedal, a casing intermediate the arm means and the pedal fixed to rock the arm means, said casing having three separated chambers therein open to atmosphere a. xed piston in one end chamber, a Valve movable a limited extent in tl'ie other end chamber and operatively connected with said pedal, said valve having passage lmeans for establishing communication between the valve chamber and the other two chambers, a physical" reaction piston in the intermediate chamber fixed on the valve, and a connection between the enginemanifold and the Valve chamber.

4. In a motor vehicle, the combination with brake control mechanism including across rod and spring releasing means, and an'engineintake manifold, of actuator means for the brake control mechanism comprising arm means xed to the brake cross rod, a pivoted physical operable part, a casing operatively connected to rock said arm means and apply the brake mechanism against the action of the spring releasing means, said casing having three aligned separated chambers therein each open at one end to atmosphere, a xed piston in the chamber adjacent `the portion of the casing connected with the arm means, a valve movable'a limited extent in the chamber at the end of the casing opposite the fixed piston, means operatively connecting the valve with the' physical operable part, a connection between the engineintake manifold andthe valve chamber, a valve stem extending into the intermediate physical reaction chamber and the fixed piston chamber, and a piston in the intermediate chamber fixed on the valve stein, said valve and stem having passage means connecting the ends of the reaction chamber and xed piston chamber on the opposite sides of the pistons to the ends open to atmosphere with the valve chamber and said valve controlling connection of its chamber with atmosphere or the intake manifold.

5. In a motor vehicle, .the combination with brake control mechanism including a cross rodand spring ,releasing means, and an engine intake manifold, o'f actuator means for the brake y control mechanism comprising arm means fixed vto the brakecross rod, a pivoted physicaloperable part, acasing operatively. connected to rsalti arm means tolap'ply the brake mechanismaga'inst. the action 0'f the spring releasing me'ans,A said.

'casing Y having a pair Vof valigned chambers; therein. each open at one end to atmosphere,` a ilxed piston in'` the chamber adjacentthe portion of the casing connected with the arm means, a valve movable a limited'extent in the otherchamber a pair'of spaced annular'shoulde'r's 1in the valve chamber,v a valve stemjoperatively connected with the physical operable parta connectionbetween the engine intake manifold andthe valve chamber, said valve being movablea limited extentfinits chamber to engage shoulders for opening` yorshutting oit the chambertoatniosphere or to the corinectionwith the intake vmanifold,

- and means associatedwwith said valve stem (and said casing limiting the movement of the valve relativeto the casing;

said ivalve 'including passage means 'extending from'its chamber to the end of thefnxed piston chamber opposite the end open todjatmosphere,

6.Ina motor vehicle, Y brake control mechanism including va cross' rod and spring releasing means, and an'intakemanifold, of actuator means for thel brake control` mechanism comprising arm means fixed to the brake cross rod,y a pivoted physicaloperable part,

a casing' operatively connected at. one end to rock. said arm means and apply the brakemechanism.. against the action oi the spring releasing means, said casing having three aligned chambers sep4 arated bya pair of transversely extending walls `and being open. at one end to atmosphere, said transversely extending walls having axially aligned bearings, auxed piston inthe chamber adjacent the end'of Athe casing connected to the arm means, a valveymovable a limited extent in the chamber at lthe end of the caSing'remOte'IrOm Y the `fixed piston chamber, means1operativel`y, connecting the .valve with the physical operable f manifold.

part, a connectionfbetwee'n the engine intake manifold and the valve chamber, a valve stem extendingv through the bearings inthe transver'sely extending walls ofrthe casingQand a pistonin the kintermediate chamber fixed on they valve stem, saidvalveand stem having passage means leading from .the valve' chamber to the ends of the piston chambers remotev kfrom the endsA open to atmosphere and .said valveV con.r

trolling' the 'connection Yci! its chamber with atmosphere or Athe connection with theintake 7."In a motor vehicle,`the 'combination with brake control lmechanismfincluding a cross rodand spring releasingmeans, and an intakeA manifold, of actuator means for the brake .controh mechanism comprising arm means fixed to the brake' cross rod,'a vpivoted physicaloperable part,

a casing operatively connected. to,v rock said -arm means andapply the brake `mecl'ianism against the action of'fthelispring releasing means,"Y said casing having three aligned separated chambers therein each open aty one end to atmosphere, a fixed piston inthe chamber adjacent the por@ tion of the fcasing connected with the arm means, a connection-between the chamberzat the end of the casing remote from the 'lxed piston chamber with the intake manifold, 'a valve -movable a-limitedextent in thechamber connected with the intake manifgid, said valve having rub- 1 berfring means on its marginal Vfaces adapted to lseat againstl the casing to seal thechamber from atmosphere or -the connection withv the intake the .combination fwith manifold, means operatively connecting ythe yvalve withy the physical operable part,m a valve'fstem xed 0n the valve/Siem, Said Y2- Ive andstem Tha ing passagemeans connecting the vreaction cha'm;

extending intp meintermediate nhysieaifreac.

tion chamber and theldxedpistonchamber, a piston in. the intermediate l' vreaction'ehalriibfel",

berfand the xefd lpiston'-chanibei attire,"'ends'- chamber.l

opposite those 'open toV atrinfisphel,:with- *wel* mv e. Y A.

.,.,3.In a motor vehicle, the combination, with; l 'brakecontrol mechanism indudmg' -a cm 'mdr `fold, of actuator means for` the gbrake'control.V

brake cross rod, a pivoted, physical operable I mechanism comprising arm means fixed to the part, a casing operatively connectedto rockwsaid arm means and vapply the brake "mechanism against the action ofthe 4spring releasing means, said caslnghaving' three'aligned separated chambers therein each open at oneend rto atmosthe portion of the'casing connected with the arm means :aifvalve movable a limitedextent inthe chamber at the endoithe casing opposite the phere,a'fi`xed piston inthe chamber adjacent' fixed piston, stems extending from opposite4 faces i of the valve, means connecting one ofthe stems' with the physical operablepart, the other valve y stem extending through the intermediate chamber andV into the Ailxecl piston chamber, a con nection between the engine intake manifold and. the valve chamber, and aplston in the intermediate chamberjxed on 'the valve stem, said valve and the valve stem extending'through the intermediate chamber` and into the Afixed piston chamber having passage means thereinconnecting said chamberson-the opposite side of the pis- `tons from the side open to atmosphere withsaid valve chamber. n ,i 9. In a motor vehicle, the combination with brake control meehanismf including a cross rodl and spring releasing means, and an intake manifold, of actuator` Vmeans for the 'brake control `mechanism comprising arm-means nxed'lto the brake cross rod, a pivotedphysical operable part,

a casing operativelyconnected to rock-said arm means-and apply the lbrake .mechanism against v the action of the springreleasing means, said casing having three aligned separatedy chambers therein each open at oneend to atmosphere, a

ixed 'piston in the chamber adjacent the portionrl` oi' the casing connectedY with the arm means, a

' valve movable a limited extent in the chamber at the end of the casing. opposite the xed vpiston chamber, means operatively connecting the valve l with the physical operable part, a connection betweenthe engineintake 'manifoldand the valve chamber, avalve stem extending throughk the chamber, 'and a piston in the intermediate chamintermediate chamber and into 4the fixed piston bernxed on the valve/stem, said vvalve having radialpassage's therein opening through the pe-k riphery and communicating Awith Aa passage extendinglthrougb the valve stem, said stem having openings communicating with said intermediate chamber on the side of the piston therein opposite the sideopen to atmosphere.

10Q-Iny a motor vehicle',;'the combination' with V brake control mechanism including a cross `rod and spring releasing'means,and an intake mani'- fold, ofiactuatorlmeans for thevbrake control I mechanism comprising arm means fined to'the vbrake cross rod, a pivoted physical operable part,

a casing operatively connected to rock said arm means and apply the brake mechanism 'against'` the action of the spring releasing means, said casing having three aligned separated chambers therein each open at one end to atmosphere. a fixed piston in the chamber adjacent the portion of the casing connected with the arm means, a valve movable a limited extent in the chamber at the end of the casing opposite the xed piston chamber, means operatively connecting the valvel with the physical operable part, a connection between the engine intake manifold and the valve chamber, a valve stem extending into the intermediate chamber and the fixed piston chamber, a piston in the intermediate chamber fixed on th'e valve stem, said valve and stem having passage means connecting the ends of the intermediate chamber and the fixed piston chamber remote from the ends open to atmosphere with the valve chamber and said valvel controlling communication of its chamber with atmosphere or the intake manifold connection. and a spring in the valve chamber urging the valve into position opening the chamber to atmosphere.

11. Mechanism for actuating a motor vehicle element comprising a casing having three separated aligned chambers therein open to atmosphere, movable means inth'e casing forming a passage adapted to open to said three separated chambers, a xed piston in one of the end chambers, a valve on said means movable a limited extent in the other of the end chambers, said valve having passage means therein communicating with the passage in said movable means for establishing communication between the valve chamber and the other two chambers, a reaction piston in the intermediate chamber fixed to said passage forming means and movable therewith, physically operable means connected with said passage forming means, and a suction connection communicating with the valve chambers.

PETER F. ROSSMANN. 

